diff options
| -rw-r--r-- | src/plugins/platforms/windows/qwindowsglcontext.cpp | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/src/plugins/platforms/windows/qwindowsglcontext.cpp b/src/plugins/platforms/windows/qwindowsglcontext.cpp index da3e2a6a6a..ae66ef8a3d 100644 --- a/src/plugins/platforms/windows/qwindowsglcontext.cpp +++ b/src/plugins/platforms/windows/qwindowsglcontext.cpp @@ -1052,8 +1052,16 @@ bool QWindowsGLContext::makeCurrent(QPlatformSurface *surface) // Do we already have a DC entry for that window? QWindowsWindow *window = static_cast<QWindowsWindow *>(surface); const HWND hwnd = window->handle(); - if (const QOpenGLContextData *contextData = findByHWND(m_windowContexts, hwnd)) + if (const QOpenGLContextData *contextData = findByHWND(m_windowContexts, hwnd)) { + // Repeated calls to wglMakeCurrent when vsync is enabled in the driver will + // often result in 100% cpuload. This check is cheap and avoids the problem. + // This is reproducable on NVidia cards and Intel onboard chips. + if (wglGetCurrentContext() == contextData->renderingContext + && wglGetCurrentDC() == contextData->hdc) { + return true; + } return wglMakeCurrent(contextData->hdc, contextData->renderingContext); + } // Create a new entry. const QOpenGLContextData newContext(m_renderingContext, hwnd, GetDC(hwnd)); if (!newContext.hdc) |